Tuesday, 26 August 2014

A Summer Summary

It's been a very busy summer so sticking with Rachel's trend of timely blogging, I decided to wait til the Himalayan Balsam had started to go over before kicking off the waders and getting back into the office to contribute to the blog. When you see the amount we've achieved in the last few months I think you'll agree that it was worth the wait! 

We’ve been re-surfacing woodland paths, creating new habitats in the form of bug hotels and reptile hibernacula, not to mention keeping up with the Great Gatsbees – our thriving Honey Bee population. As always, however, one of the most important jobs has been trying to control the spread of Himalayan Balsam (Glandulifera impatiens) across Gatwick’s conservation zones and beyond.

This impressive plant can grow up to eight feet in a little over sixteen weeks, using an explosive mechanism in its seed heads to disperse seeds far and wide, before spreading quickly to dominate river banks, displacing native flora in the process. If you’d like to find out more, there’s a helpful article on the Sussex Wildlife Trust website here: http://www.sussexwildlifetrust.org.uk/blog/2014/07/greenspace-invader/

Himalayan Balsam in flower
Himalayan Balsam’s dependence on river systems for seed dispersal means that low-lying areas like Gatwick Airport, which is intersected by a number of water courses such as the River Mole, Gatwick Stream, Crawters Brook and Mans Brook, receives a constant influx of seeds throughout the summer. This makes the job of controlling its spread all the more important and begs the difficult question; where do we start?

After much deliberation (and some blindfolded pointing at a map), we decided to begin our battle at Povey Cross in the North West Zone with a team from Gatwick Airport’s Engineering and Asset Integration Department. On a scorching hot day at the end of June, this nine-strong group got stuck in, removing plants over an incredible 700 meter stretch of the banks of the Mole.

Engineering and Asset Integration with Balsam casualties at Povey cross
A little over a week later, volunteers from Southern Gas Networks took up the mantle in Horleyland Wood where Balsam had taken up residence in dense patches under the woodland canopy, encroaching from the adjoining Gatwick Stream and sewage treatment works. The following day reinforcements arrived in the form of GGP’s youth rangers. They set to work with boundless energy, pulling back more valuable habitat from the Balsam’s clutches.

Southern Gas came ready for action with matching overalls.
Youth Rangers at Horleyland wood, accompanied by one slightly less youthful ecologist.

By early July it was time to call in the elite squadron and GGPs weekly volunteer group got to grips with the Balsam in Riverside Garden Park, Horley, where the Gatwick stream joins the river Mole. Undeterred by the towering Balsam-covered banks, they put in a tremendous effort over two long and very hot days. Using ladders to scale the steep banks, they tirelessly removed plant after plant. This resulted in at least one volunteer taking a bath in the cool, calming waters of the Gatwick Stream. Despite these setbacks, their hard work paid off and we managed to clear the majority of the Balsam from the park, downstream from the underpass in the south-eastern corner.

GGP Volunteers tackle towering Balsam at Riverside
A final sweep of Riverside was carried out by a group of EDF office staff who came all the way from London to join the fight. The team were very thorough and spent the morning working away from the stream, removing any stragglers in the woodland edges where seed had been carried by winter flood waters. As the day wore on and we worked our way into open grassland, it became apparent that we were going to need a change of plan. Fueled by the scorching summer temperatures, much of the Balsam in these open areas was already setting seed and too much disruption at this stage would only facilitate its spread.

EDF's London team at Riverside
We proceeded carefully, using scissors and secateurs to carefully snip all of the seed pods into bin bags before ripping out the remainder of the plant. Six bin bags of seed were removed and prevented from entering the catchment that day.

As you can see from the map below we have made a big impact this year, and its all thanks to the fantastic work of our ever-growing volunteer network. All our volunteers have proved willing and able and always up for a challenge.  

But as I said earlier, it hasn’t been all about Balsam this summer. I’d like to say a heartfelt thank you to everyone who has turned out to help with our many projects. And just to prove it, here are a few more pictures.
UK Power Networks and the huge pile of rubbish they cleared from Horleyland pond back in April.
Dave and Stefan "discuss" how best to lay geotextiles while building a footpath in Upper Pickets wood.

Rachel's mum, Sue and ecologist Natalie get the job done with a little less "discussion"
(I'm not sure who that slacker is trying to sneak into shot)

Another gang from UK Power Networks turned out in force in June, working competitively on woodland and grassland footpaths

 And finally, the Insect Hotel has been slowly coming together over the summer with the help of Donald and Peter.

Not long until our programme of autumn works starts up again!

Wednesday, 6 August 2014

Honeybee freeloaders

Following Simpson's lead I've decided to have a try at this beekeeping thing. During a busy field season it means I get home even later, but on the other hand it is an excellent way to unwind.

The well-guarded hive entrance of the European Honey Bee (Apis mellifera). It is incredibly therapeutic to just sit and watch the comings-and-goings of  workers and drones.

We now have several hives which are packed to the rafters with honey and bee larvae, attracting a menagerie of predators and parasites. This means that during my new hobby, I still get to record new species!

Greater Wax Moth (Galleria mellonella)

The Greater Wax Moth is a new one for me; this individual met her demise in the top section of the hive (perhaps after being stung or balled to death by the workers). It lays its eggs on the waxy honeycomb, which then hatch into caterpillars and bore tunnels through the cells, feeding on the wax and other bee-substances. They can also burrow into the wood of the hive, so when present in high numbers they can cause a lot of damage to the structure.

I'm quite please with this pic. That red 'welt' on the top of the
abdomen is an individual Varroa Mite (Varroa destructor)

Varroa destructor is an apt name for this mite, indicating just how much beekeepers love them... Not only does this blood-feeding arachnid weaken the individual bees by sucking out their life-force, they spread several bee viruses and are incredibly difficult to contain. However, we do not intervene unless an infection is particularly severe. Symptoms can include stunted, scruffy, deformed wings and unsteady, drunk-looking bees. Having this mite must be like hanging out with your impulsive, booze-hound flatmate on a night out in town (not of course referring to anyone I live with right now).

 German Wasp (Vespula germanica)

Social wasps can be a right pain at this time of year (I need not tell). Attracted to the scent of the wonderful honey stores, as soon we lift the lid off the hive, then they appear, persistently pesky. They also scavenge the dead and dying bees from the ground around the hive; not such a bad thing in terms of good house keeping and removing infected individuals. This female German Wasp found a dying worker Honey Bee and set to it with her strong mandibles... There was an audible 'click' as she decapitated it!

Fencepost Jumper (Marpissa muscosa)

It seems that almost every time we start a check of the hives, a Marpissa jumping spider will pop out onto the side to see what all the fuss is about. They probably just use the hives as a well-defended shelter and are unlikely to bother the bees. Perhaps they love the sweet smell of honey and cedar wood as much as we do.

Beekeeper (Homo sapiens)

Of course, not forgetting those ultimate freeloaders! Which reminds me, it is about time I enter my first record for Homo sapiens into iRecord... Egotistical perhaps to submit myself as a specimen?